farmquilter, you can probably add subscriptions right on your Roku. Go to the Roku home screen, find the Roku Channel Store (I think you just scroll down on the left side of the home screen), and click on Hulu or whatever else you want to add. Or you can go to hulu.com to sign up. I think you can also go to the Roku Channel Store online and sign up there:
https://channelstore.roku.com/browse after logging in with your Roku ID.
My dh and I don't use Hulu, but my daughter and her boyfriend use it. You can see what shows are on it here:
http://www.hulu.com/start/content (note there are 191 pages there! be sure to check the "currently on air" filter to get it down to 11 pages). Unlike Netflix, Hulu shows include commercials and there's no easy way to fast forward through them.
My dh and I really like Acorn, which is only $5/month. There are quite a few different shows and the accents vary. You could try it out for a month and cancel if you don't like it. We found a lot of shows there to watch, including some from New Zealand and Australia (those accents tend to be harder to understand than British, but we got used to them). Acorn does not have anything like what is on the Hallmark channel or the HGTV, though. I think you would have to subscribe to Sling to get those channels.